An extensive damage evaluation and chemistry optimization for lower damage and lower k-value on Porous MSQ Dual Damascene Etch/Ash process

摘要

When applying Low-k material to Cu interconnect systems, many issues related not only to technology but also CoO/CoC, should be resolved. In this paper, we are reporting solutions for several issues from the etching and ashing process point of view. For Etching, Duo248~(TM) approach ( Duo 248~(TM) from Honeywell is covered under US patent #6,268,457) that is sacrificial material for Via 1st approach applied from Honeywell is proposed. For ashing, Hybrid Ashing that is all in one approach (Etching and Ashing process same chamber continuously) is proposed. The target of those approaches will be below 65nm.